To define how often a user needs to visit the site, enter a number in the "Return Visit Count" text field. Select a comparator to define if the number of visits made by the user should be "equal" to, "greater than or equal to", "less than or equal to", "greater than", or "less than" the number you entered.
To define the time period the visits should have appeared in, select the "Timeframe Constraints" tab. Enter the information needed in the tab in order to define the time period.